Kinetic studies of specific solvent effect on the thermal isomerization of palladium dithizonate in toluene-alcohol mixtures

The kinetics of the thermal isomerization of palladium dithizonate (Pd(HD_z)₂) in the binary mixture of toluene and alcohols has been studied. In the solvent effects on the Pd(HD_z)₂ isomerization rates, we found that the maximum lies in the range x = 0.02 to approximately 0.2 (x represents the mole fraction of alcohols). The experimental kinetic data for the specific solvent effect with maximum can be reproduced well by taking into account hydrogen bonding and coordination of alcohols with Pd(HD_z)₂. The rate constants for the thermal isomerization of Pd(HD_z)₂ involving hydrogen bonding and the coordinate interaction with 1-butanol are evaluated.